Reassessing the importance of the colour-singlet contributions to direct J/psi+W production at the LHC and the Tevatron

Abstract

We show that the colour-singlet contributions to the hadroproduction of J/psi in association with a W boson are sizable, if not dominant over the colour-octet contributions. They are of two kinds, sg -> J/psi + c + W at alpha^3_S alpha and q q'-bar -> gamma*/Z* W -> J/psi W at order alpha^3. These have not been considered in the literature until now. Our conclusion is that the hadroproduction of a J/psi in association with a W boson cannot be claimed as a clean probe of the colour-octet mechanism. The rate are small even at the LHC and it will be very delicate to disentangle the colour-octet contributions from the sizable colour-singlet ones and from the possibly large double-parton-scattering contributions. During this analysis, we have also noted that, for reactions such as the production of a J/psi by light quark-antiquark fusion, the colour-singlet contribution via an off-shell photon is of the order of the expectation from the colour-octet contribution via an off-shell gluon. This is relevant for inclusive production at low energies close to the threshold. Such an observation also likely extends to other processes naturally involving light-quark annihilation.

5 pages, 8 figures, LaTeX (uses elsarticle.cls). v2 (as published in PLB): slight rewordings; discussion on the contributions from the 3 body decay W -> J/psi+mu+nu_mu, from double-parton scatterings and from chi(c) decay added; plotting error in Figs 2 & 3 fixed

References in corpus (14)

• Heavy quarkonium: progress, puzzles, and opportunities
• QCD corrections to J/psi and Upsilon production at hadron colliders
• Polarization for Prompt J/psi, psi(2s) production at the Tevatron and LHC
• Upsilon production at the Tevatron and the LHC
• Measurement of hard double-parton interactions in W->lv+ 2 jet events at sqrt(s)=7 TeV with the ATLAS detector
• J/psi, psi' and Upsilon Production at Hadron Colliders: a review
• QCD corrections to J/psi polarization of hadronproduction at Tevatron and LHC
• HELAC-Onia: an automatic matrix element generator for heavy quarkonium physics
• On the mechanisms of heavy-quarkonium hadroproduction
• Hadroproduction of J/psi and Upsilon in association with a heavy-quark pair
• QCD corrections to polarization of J/ψand Υat Fermilab Tevatron and CERN LHC
• Next-to-Leading-Order QCD corrections to J/ψ(Υ)+γproduction at the LHC
• Real next-to-next-to-leading-order QCD corrections to J/psi and Upsilon hadroproduction in association with a photon
• QCD corrections to $J/\psi$ production in association with a $W$-boson at the LHC

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